void addstudent(struct studentNode* list);
void printList(struct studentNode* listHeadNode);
int check(struct studentNode* list,struct student tempData);
void checkstudent();
void showMessage();
void quit();
void addStudent(struct studentNode* list);
void sortStudent(struct studentNode* list);
void queryStudent(struct studentNode* list);
void deleteStudent(struct studentNode* list);
void queryStudentClassification(struct studentNode* list);
void updateStudentInfo(struct studentNode* list);
void userhelp();
void changepassword();
int isUserValid(char userAcount[],char userPassword[]);
void changecolor();
